Haplont

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Haplonts are organisms whose cell nuclei contain a simple ( haploid ) set of chromosomes. Only the zygote of these organisms that occurs in the course of sexual reproduction has a double set of chromosomes , i.e. it is diploid . This is based on the fact that the zygote formed during fertilization (union of two haploid gametes and fusion of the cell nuclei ( karyogamy )) next carries out meiosis (reduction division) during its further development , from which haploid nuclei arise again.

The haplonts include many fungi (only in the case of the sac fungi there is a normal nucleus division ( mitosis ) between karyogamy and meiosis in the diploid phase ), many algae and some animal protozoa , especially flagellates . The opposite case is represented by the Diplonts , in which all cells with the exception of the gametes ( egg cells and sperm ) are diploid. This includes humans and all other metazoa . Third, there are diplohaplons in which haploid and diploid generations alternate. This includes the land plants ( Embryophyta ), whereby the haploid generation is only evident in mosses and ferns .

literature

D. Sadava, DM Hillis, HC Heller, MR Berenbaum: Purves biologist ; Spektrum Akademischer Verlag, 9th edition 2011; ISBN 978-3-8274-2650-5 ; Pages 751 ff.

Web links

Wiktionary: Haplont  - explanations of meanings, word origins, synonyms, translations